Fusion protein of interleukin 2 and application thereof in ibd

Abstract

Disclosed is a fusion protein of interleukin 2 and an application thereof in the treatment or prevention of inflammatory bowel disease, characterized in that the fusion protein comprises: human interleukin 2 or a variant thereof, and human serum albumin or a variant thereof.

1 . A fusion protein of interleukin 2, comprising: a human interleukin 2 or its variant; and human serum albumin or its variant, wherein the human interleukin 2 or its variants includes: an amino acid sequence as shown in SEQ ID NO: 1; or, an amino acid sequence having at least 90% sequence identity with the amino acid sequence as shown in SEQ ID NO:1;
 the human serum albumin or its variants includes: an amino acid sequence as shown in SEQ ID NO: 2; or, an amino acid sequence having at least 90% sequence identity with the amino acid sequence shown in SEQ ID NO:2.   
     
     
         2 . The fusion protein according to  claim 1 , wherein the fusion protein includes the amino acid sequence as shown in SEQ ID NO: 1 and the amino acid sequence as shown in SEQ ID NO:2;
 preferably, the amino acid at position 125 of the amino acid sequence as shown in SEQ ID NO:1 is not cysteine;   preferably, the amino acid at position 125 of the amino acid sequence as shown in SEQ ID NO:1 is replaced with serine or alanine.   
     
     
         3 . The fusion protein according to  claim 1 , wherein the human interleukin 2 or its variant is connected to the human serum albumin or its variant directly or via a linking peptide. 
     
     
         4 . The fusion protein according to  claim 3 , wherein the linking peptide has a general formula of (GnS) m, in which n or m is an integer selected from 1 to 10;
 preferably, the linking peptide has a general formula of (GnS) m, in which n is an integer selected from 1 to 4, and m is an integer selected from 0 to 3.   
     
     
         5 . The fusion protein according to  claim 1 , wherein the fusion protein has an amino acid sequence as shown in SEQ ID NO:4. 
     
     
         6 . An isolated nucleic acid molecule encoding the fusion protein as defined in  claim 1 . 
     
     
         7 . An expression system comprising a CHO cell which contains the nucleic acid molecule as defined in  claim 6 ,
 preferably, the expression system is CHO0-K1 cell, which is deposited in China General Microbiological Culture Collection Center on May 26, 2022, under CGMCC No. 45173.   
     
     
         8 . A pharmaceutical composition comprising the fusion protein as defined in  claim 1 , and a pharmaceutically acceptable carrier. 
     
     
         9 . The pharmaceutical composition according to  claim 8 , wherein the pharmaceutical composition is in a dosage form of injection, tablet or capsule;
 preferably, the dosage form is selected from solution for injection or lyophilized powder for injection;   preferably, the carrier is selected from excipient, diluent, filler, binder, wetting agent, disintegrant, absorption enhancer, surfactant, absorptive support, and/or stabilizer.   
     
     
         10 . A method for treating or preventing inflammatory bowel disease (IBD), comprising administrating to a subject of an effective amount of the fusion protein as defined in  claim 1 . 
     
     
         11 . The method according to  claim 10 , wherein the IBD comprise ulcerative colitis, Crohn's disease and indeterminate colitis. 
     
     
         12 . The method according to  claim 10 , wherein the fusion protein or the pharmaceutical composition is administered orally or by injection.
 preferably, the fusion protein or the pharmaceutical composition is administered by subcutaneous or intravenous infusion.   
     
     
         13 . The method according to  claim 10 , wherein the fusion protein is administered at 3×10 4  IU to 1×10 6  IU each dose;
 preferably, the pharmaceutical composition is administered at 3×10 4  IU to 1×10 6  IU each dose, as measured by the fusion protein therein. 
 
     
     
         14 . The method according to  claim 10 , which the fusion protein is administered every 7-28 days, preferably every 14-28 days;
 preferably, the pharmaceutical composition is administered every 14-28 days, preferably every 14-28 days.   
     
     
         15 . A method for treating or preventing inflammatory bowel disease (IBD), comprising administrating to a subject of an effective amount of the pharmaceutical composition as defined in  claim 8 . 
     
     
         16 . The method according to  claim 15 , wherein the IBD comprise ulcerative colitis, Crohn's disease and indeterminate colitis. 
     
     
         17 . The method according to  claim 15 , wherein the pharmaceutical composition is administered orally or by injection. preferably, the pharmaceutical composition is administered by subcutaneous or intravenous infusion. 
     
     
         18 . The method according to  claim 15 , wherein the pharmaceutical composition is administered at 3×10 4  IU to 1×10 6  IU each dose, as measured by the fusion protein therein. 
     
     
         19 . The method according to  claim 15 , which the pharmaceutical composition is administered every 14-28 days, preferably every 14-28 days.